Messages in this thread |  | | Date | Thu, 27 Sep 2001 09:16:01 +0100 | From | Russell King <> | Subject | Re: Question about ioremap and io_remap_page_range |
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On Thu, Sep 27, 2001 at 10:03:26AM +0200, Armin Schindler wrote: > virt_to_phys() is obsolete ? What should be used if I need the phys address > of a memory page ? (e.g. for mmap() remapping)
virt_to_phys is only valid on the kernel direct mapped RAM area - memory returned from kmalloc and non-highmem memory returned from get_free_page.
Since vmalloc and ioremap do not return a pointer into the direct mapped RAM area, but its own mapping, it is not valid to use virt_to_phys on these returned values, even through it might be a virtual address.
-- Russell King (rmk@arm.linux.org.uk) The developer of ARM Linux http://www.arm.linux.org.uk/personal/aboutme.html
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